U.S. patent application number 14/400012 was filed with the patent office on 2015-04-30 for aqueous coating composition having stabilized color pigments.
The applicant listed for this patent is AXALTA COATING SYSTEMS IP CO., LLC. Invention is credited to An-Gong Yeh.
Application Number | 20150119514 14/400012 |
Document ID | / |
Family ID | 49551271 |
Filed Date | 2015-04-30 |
United States Patent
Application |
20150119514 |
Kind Code |
A1 |
Yeh; An-Gong |
April 30, 2015 |
AQUEOUS COATING COMPOSITION HAVING STABILIZED COLOR PIGMENTS
Abstract
A stabilized color pigment dispersion includes a phosphated
polymer, a color pigment stabilized in the phosphated polymer, and
an aqueous carrier. The color pigment comprises one or more oxide
color pigments and is essentially free from metallic pigments. The
stabilized color pigment dispersion comprises in a range of from
about 20% to about 80% of water, percentage based on the total
weight of the stabilized color pigment dispersion.
Inventors: |
Yeh; An-Gong; (Broomall,
PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
AXALTA COATING SYSTEMS IP CO., LLC |
Wilmington |
DE |
US |
|
|
Family ID: |
49551271 |
Appl. No.: |
14/400012 |
Filed: |
May 9, 2013 |
PCT Filed: |
May 9, 2013 |
PCT NO: |
PCT/US2013/040315 |
371 Date: |
November 10, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61645881 |
May 11, 2012 |
|
|
|
Current U.S.
Class: |
524/431 ;
524/504 |
Current CPC
Class: |
C08L 2201/54 20130101;
C09D 7/41 20180101; C09B 67/0085 20130101; C09D 201/02 20130101;
C09D 17/007 20130101; C09D 143/02 20130101; C09D 7/65 20180101;
C09D 17/002 20130101 |
Class at
Publication: |
524/431 ;
524/504 |
International
Class: |
C09D 17/00 20060101
C09D017/00 |
Claims
1. A stabilized color pigment dispersion comprising: a phosphated
polymer; a color pigment stabilized in the phosphated polymer, the
color pigment comprising one or more oxide color pigments and
essentially free from metallic pigments; and an aqueous carrier;
wherein the stabilized color pigment dispersion comprises in a
range of from about 20% to about 80% of water, percentage based on
the total weight of the stabilized color pigment dispersion.
2. The stabilized color pigment dispersion of claim 1, wherein the
phosphated polymer is a phosphated graft copolymer, a phosphated
block copolymer, a phosphated linear polymer, a phosphated branched
polymer, or a combination thereof.
3. The stabilized color pigment dispersion of claim 1, wherein the
color pigment comprises one or more iron oxide color pigments.
4. The stabilized color pigment dispersion of claim 1 further
comprising one or more organic solvents.
5. The stabilized color pigment dispersion of claim 1, wherein the
phosphated polymer further comprises one or more functional groups
selected from hydroxyl groups, epoxy groups, carboxyl groups, and a
combination thereof.
6. An aqueous coating composition comprising: a stabilized color
pigment dispersion comprising: a phosphated polymer; a color
pigment stabilized in the phosphated polymer, the color pigment
comprising one or more oxide color pigments and essentially free
from metallic pigments; and an aqueous carrier; wherein the
stabilized color pigment dispersion comprises in a range of from
about 20% to about 80% of water, percentage based on the total
weight of the stabilized color pigment dispersion. a metallic
pigments; and a coating binder component; wherein the stabilized
color pigment dispersion and the metallic pigment are mixed in the
coating binder component; and the aqueous coating composition
comprises in a range of from about 20% to about 80% of water,
percentage based on the total weight of the aqueous coating
composition.
7. The aqueous coating composition of claim 6, wherein the metallic
pigment comprises an aluminum pigment.
8. The aqueous coating composition of claim 6, wherein the coating
binder component comprises one or more acrylic polymers, polyester
polymers, latex polymers, polyurethane polymers, or a combination
thereof.
9. The aqueous coating composition of claim 6, wherein the coating
binder component comprises one or more functional groups selected
from hydroxyl groups, epoxy groups, carboxyl groups, and a
combination thereof.
10. The aqueous coating composition of claim 6 further comprising
one or more organic solvents.
11. (canceled)
12. (canceled)
13. (canceled)
14. A process for forming a coating composition, the process
comprising the steps of: forming a stabilized color pigment
dispersion by stabilizing a color pigment with a phosphated polymer
in an aqueous carrier, wherein the color pigment comprises one or
more oxide color pigments and is essentially free from metallic
pigments, wherein the stabilized color pigment dispersion comprises
in a range of from about 20% to about 80% of water, percentage
based on the total weight of the stabilized color pigment
dispersion; and mixing the stabilized color pigment dispersion with
a coating binder component and an aluminum pigment to form the
coating composition.
15. The process of claim 14, wherein the phosphated polymer is a
phosphated graft copolymer, a phosphated block copolymer, a
phosphated linear polymer, a phosphated branched polymer, or a
combination thereof.
16. The process of claim 14 further comprising the step of mixing
one or more organic solvents into the coating composition.
17. The process of claim 14, wherein the color pigment comprises
one or more iron oxide color pigments.
18. The process of claim 14, wherein the phosphated polymer further
comprises one or more functional groups selected from hydroxyl
groups, epoxy groups, carboxyl groups, and a combination
thereof.
19. (canceled)
20. (canceled)
21. (canceled)
22. (canceled)
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a U.S. National-Stage entry under 35
U.S.C. .sctn.371 based on International Application No.
PCT/US2013/040315, filed May 9, 2013, which was published under PCT
Article 21(2) and which claims priority to U.S. Provisional
Application No. 61/645,881, filed May 11, 2012, which are all
hereby incorporated in their entirety by reference.
TECHNICAL FIELD
[0002] The present disclosure is directed to a stabilized color
pigment dispersion. This disclosure is further directed to a
coating composition comprising the stabilized color pigment
dispersion and metallic pigments, such as aluminum flakes.
BACKGROUND
[0003] Metallic pigments such as aluminum flake pigments in coating
compositions can be used in finishes, such as exterior finishes for
automobiles and trucks, to provide the finishes with metallic
glamour. There are relatively few problems with the addition of
these metallic flakes by conventional methods to solvent based
coating compositions. In waterborne compositions, however, the
metallic flakes, in particular, aluminum flakes, can react with
water and other constituents present in the coating composition
causing flake deterioration and can cause the evolution of gas. In
addition, finishes formed with such coatings have a reduced
brightness and/or color saturation.
[0004] Accordingly, it is desirable to provide coatings having
stable metallic pigments for long term stability and prevention of
gassing. Furthermore, other desirable features and characteristics
of the present invention will become apparent from the subsequent
detailed description and the appended claims, taken in conjunction
with the accompanying background.
SUMMARY
[0005] In accordance with an exemplary embodiment, a stabilized
color pigment dispersion comprises:
[0006] a phosphated polymer;
[0007] a color pigment stabilized in the phosphated polymer, the
color pigment comprising an oxide color pigment and essentially
free from metallic pigments; and
[0008] an aqueous carrier;
[0009] wherein the stabilized color pigment dispersion comprises in
a range of from about 20% to about 80% of water, percentage based
on the total weight of the stabilized color pigment dispersion.
[0010] In accordance with another exemplary embodiment, an aqueous
coating composition comprises:
[0011] the stabilized color pigment dispersion disclosed
herein;
[0012] a metallic pigment; and
[0013] a coating binder component; wherein
[0014] the stabilized color pigment dispersion and the metallic
pigment are mixed in the coating binder component; and
[0015] the aqueous coating composition comprises in a range of from
about 20% to about 80% of water, percentage based on the total
weight of the aqueous coating composition.
[0016] In a further exemplary embodiment, a process for forming a
coating composition comprises the steps of:
[0017] forming a stabilized color pigment dispersion by stabilizing
a color pigment with a phosphated polymer in an aqueous carrier,
the color pigment comprising an oxide color pigment and essentially
free from metallic pigments, wherein the stabilized color pigment
dispersion comprises in a range of from about 20% to about 80% of
water, percentage based on the total weight of the stabilized color
pigment dispersion; and
[0018] mixing the stabilized color pigment dispersion with a
coating binder component and an aluminum pigment to form the
coating composition.
[0019] Another exemplary embodiment is directed to a coating
process for coating a substrate with a coating composition, the
coating process comprising the steps of:
[0020] providing the coating composition disclosed herein; and
[0021] applying the coating composition over the substrate to form
a wet metallic color coat layer thereon.
DETAILED DESCRIPTION
[0022] The features and advantages of the present invention will be
more readily understood, by those of ordinary skill in the art,
from reading the following detailed description. It is to be
appreciated that certain features of the invention, which are, for
clarity, described above and below in the context of separate
embodiments, may also be provided in combination in a single
embodiment. Conversely, various features of the invention that are,
for brevity, described in the context of a single embodiment, may
also be provided separately or in any sub-combination. In addition,
references in the singular may also include the plural (for
example, "a" and "an" may refer to one, or one or more) unless the
context specifically states otherwise.
[0023] The use of numerical values in the various ranges specified
in this application, unless expressly indicated otherwise, are
stated as approximations as though the minimum and maximum values
within the stated ranges were both proceeded by the word "about."
In this manner, slight variations above and below the stated ranges
can be used to achieve substantially the same results as values
within the ranges. Also, the disclosure of these ranges is intended
as a continuous range including every value between the minimum and
maximum values.
[0024] As used herein:
[0025] The term "dye" means a colorant or colorants that produce
color or colors and is usually soluble in a coating
composition.
[0026] The term "color pigment" or "color pigments" used herein
refers to a colorant or colorants that produce color or colors and
is usually not soluble in a coating composition. A color pigment
can be from natural and synthetic sources and made of organic or
inorganic constituents.
[0027] The term "effect pigment" or "effect pigments" refers to
pigments that produce special effects in a coating. Examples of
effect pigments can include, but not limited to, light absorbing
pigment, light scattering pigments, light interference pigments,
and light reflecting pigments. Metallic flakes, for example
aluminum flakes, can be examples of such effect pigments. The term
"gonioapparent flakes", "gonioapparent pigment" or "gonioapparent
pigments" refers to pigment or pigments pertaining to change in
color, appearance, or a combination thereof with change in
illumination angle or viewing angle. Metallic flakes, such as
aluminum flakes are examples of gonioapparent pigments.
Interference pigments or pearlescent pigments can be further
examples of gonioapparent pigments.
[0028] The term "metallic pigment", "metallic pigments", "metal
pigments" or "metal pigments" refers to particles or flakes of
nonoxidized metal or alloys used as effect pigments to produce
special effects in coatings. Examples of metallic pigments can
include metallic flakes or particles, such as aluminum flakes or
particles.
[0029] The term "oxide color pigments" or "metal oxide color
pigments" refers to natural or synthetic oxide pigments that are
compounds containing oxygen. For example, metal oxide color
pigments can include iron oxides or hydrated iron oxides that are
chemical compounds composed of iron and oxygen and can have
different colors, such as yellow oxide (Fe.sub.2O.sub.3.H.sub.2O),
brown oxide (Fe.sub.2O.sub.3.xFeO), black oxide (Fe.sub.3O.sub.4),
or red (Fe.sub.2O.sub.3) depending on the compositions. Other
oxides, such as silicon oxides, manganese oxides, aluminum oxides,
calcium oxides or magnesium oxides can also be included. The "oxide
color pigments" or "metal oxide color pigments" can be present
naturally or manufactured by a synthetic process.
[0030] This disclosure is directed to a stabilized color pigment
dispersion. The stabilized color pigment dispersion comprises:
[0031] a phosphated polymer;
[0032] a color pigment stabilized in the phosphated polymer, the
color pigment comprising an oxide color pigment and essentially
free from metallic pigments; and
[0033] an aqueous carrier;
[0034] wherein the stabilized color pigment dispersion comprises in
a range of from about 20% to about 80% of water, percentage based
on the total weight of the stabilized color pigment dispersion.
[0035] The phosphated polymer can be a phosphated graft copolymer,
a phosphated block copolymer, a phosphated linear polymer, a
phosphated branched polymer, or a combination thereof
[0036] The phosphated polymer can be a phosphate linear polymer
polymerized from unsaturated monomers in one example, a phosphate
graft copolymer in another example, a phosphate block copolymer in
yet another example, a phosphate branched copolymer in yet another
example, or a combination thereof. The phosphated polymer can
further comprise one or more functional groups selected from
hydroxyl groups, epoxy groups, carboxyl groups, or a combination
thereof. In a further example, phosphate styrene/allyl alcohol
copolymer disclosed in U.S. Pat. No. 4,675,358 can be suitable. In
a yet further example, phosphate graft copolymer disclosed in U.S.
Pat. No. 5,502,113 can be suitable.
[0037] The color pigment is stabilized in the phosphated polymer,
typically, by mixing. The color pigment can comprise one or more
oxide color pigments and is essentially free from metallic
pigments. By "essentially free", the color pigment can comprise
minor amounts of metallic pigments, typically less than about 1% of
the metallic pigments, percentage based on the total weight of the
color pigment. The color pigment can be of different colors and can
be produced naturally or manufactured by a synthetic process. The
color pigment can comprise one or more iron oxide color pigments.
Other metal oxides, non-oxide or organic color pigments, such as
silicon oxide, titanium oxides, organic azo pigments, copper
phthalocyanine, carbon black, clay, or a combination thereof, can
also be included. The color pigment can comprise in a range of from
about 5% to 100% in one example, about 10% to 100% in another
example, about 20% to 100% in yet another example, about 50% to
100% in yet another example, about 70% to 100% in yet another
example, about 90% to 100% in yet another example of one or more
iron oxide color pigments. The one or more iron oxide color
pigments can be of different colors and can be produced naturally
or manufactured by a synthetic process. The processes and
compositions disclosed herein are particularly suitable for color
pigments comprising one or more iron oxides.
[0038] The color pigment can also be dispersed first in the
presence of water by a process known to those skilled in the art to
form a color dispersion. The color dispersion can comprise in a
range of from about 20% to about 80% of water, percentage based on
the total weight of the color dispersion. The color dispersion then
can be mixed with the phosphated polymer to form the stabilized
color pigment dispersion.
[0039] The stabilized color pigment dispersion can further comprise
one or more organic solvents. Typical organic solvents suitable for
coating applications are suitable. Water soluble or water miscible
organic solvents are preferred.
[0040] This disclosure is further directed to an aqueous coating
composition. The aqueous coating composition comprises:
[0041] the stabilized color pigment dispersion disclosed
herein;
[0042] one or more metallic pigments; and
[0043] a coating binder component; wherein
[0044] the stabilized color pigment dispersion and the metallic
pigment are mixed in the coating binder component; and
[0045] the aqueous coating composition comprises in a range of from
about 20% to about 80% of water, percentage based on the total
weight of the aqueous coating composition.
[0046] The metallic pigment can comprise aluminum pigments, such as
one or more aluminum flakes or particles. The aluminum flakes or
particles can have different shapes, types, sizes, or a combination
thereof. Typically, aluminum flakes or particles can be in shapes,
types or sizes suitable for coating applications as effect
pigments.
[0047] The stabilized color pigment dispersion, the metallic
pigment, and the coating binder component can be mixed to form the
coating composition. In one example, the stabilized color pigment
dispersion and the coating binder component can be mixed first, and
then the metallic pigment can be added to form the coating
composition. In another example, the stabilized color pigment
dispersion and the metallic pigment can be mixed first, and then
the coating binder component can be added to form the coating
composition. In yet another example, the stabilized color pigment
dispersion, the metallic pigment, and the coating binder component
can be mix at same time form the coating composition.
[0048] The color dispersion can be mixed with the phosphated
polymer to form the stabilized color pigment dispersion, and
further mixed with the coating binder component to form the aqueous
coating composition.
[0049] The coating binder component can comprise one or more
acrylic polymers, polyester polymers, latex polymers, polyurethane
polymers, or a combination thereof. Typical polymers that are
suitable for coating applications can be suitable. The coating
binder component can comprise one or more functional groups
selected from hydroxyl groups, epoxy groups, carboxyl groups, or a
combination thereof, typically, on one or more of the
aforementioned polymers present in the coating binder
component.
[0050] The aqueous coating composition can further comprise one or
more organic solvents. Typical organic solvents suitable for
coating applications can be suitable. Water soluble or water
miscible organic solvents are preferred.
[0051] The aqueous coating composition can further comprise one or
more conventional pigments, coating additives, or a combination
thereof. Examples of such additives include wetting agents,
leveling and flow control agents, for example, Resiflow.RTM.S
(polybutylacrylate), BYK.RTM. 320 and 325 (high molecular weight
polyacrylates), BYK.RTM. 347 (polyether-modified siloxane) under
respective registered trademarks, leveling agents based on
(meth)acrylic homopolymers; rheological control agents; thickeners,
such as partially crosslinked polycarboxylic acid or polyurethanes;
and antifoaming agents. The additives can be used in conventional
amounts familiar to those skilled in the art.
[0052] This disclosure is further directed to a coated article
comprising a substrate and a metallic color coating layer formed
over the substrate from the coating composition disclosed herein.
The substrate can be a vehicle, vehicle parts, or a combination
thereof. The substrate can also be other industrial or consumer
articles, such as appliances, power tools, furniture, rails, tanks,
etc.
[0053] The metallic color coating layer can be coated over a primer
coating layer coated over the substrate. In one example, a
substrate can be first coated with one or more primer layers and
then subsequently coated over the primer layer with the aqueous
coating composition disclosed herein.
[0054] This disclosure is even further directed to a process for
forming a coating composition. In an exemplary embodiment, the
process comprises the steps of:
[0055] forming a stabilized color pigment dispersion by stabilizing
a color pigment with a phosphated polymer in an aqueous carrier,
the color pigment comprising an oxide color pigment and essentially
free from metallic pigments, wherein the stabilized color pigment
dispersion comprises in a range of from about 20% to about 80% of
water, percentage based on the total weight of the stabilized color
pigment dispersion; and
[0056] mixing the stabilized color pigment dispersion with a
coating binder component and an aluminum pigment to form the
coating composition.
[0057] In the aforementioned process, the phosphated polymer can be
a phosphated graft copolymer, a phosphated block copolymer, a
phosphated linear polymer, a phosphated branched polymer, or a
combination thereof, as described previously. The phosphated
polymer can further comprise one or more functional groups selected
from hydroxyl groups, epoxy groups, carboxyl groups, or a
combination thereof
[0058] As mentioned above, the color pigment can also be dispersed
into aforementioned color dispersion. The color dispersion then can
be mixed with the phosphated polymer to form the stabilized color
pigment dispersion, and further mixed with the coating binder
component to form the aqueous coating composition.
[0059] The process can further comprise the step of mixing one or
more organic solvents into the coating composition. The
aforementioned organic solvents can be suitable.
[0060] The color pigment can comprise one or more iron oxide color
pigments as described previously.
[0061] This disclosure is further directed to a coating process for
coating a substrate with a coating composition. In an embodiment,
the coating process comprises the steps of:
[0062] providing the coating composition disclosed herein; and
[0063] applying the coating composition over the substrate to form
a wet metallic color coat layer thereon.
[0064] In one example, any of the aforementioned coating
compositions can be suitable. In another example, any of the
aforementioned coating compositions formed by the aforementioned
processes can be suitable.
[0065] In an embodiment, the coating process further comprises the
steps of:
[0066] curing the wet metallic color coat layer to form a dry
metallic color coat layer over the substrate.
[0067] The coating layer can be cured at an ambient temperature in
a range of from about 15.degree. C. to about 45.degree. C., an
elevated temperature in a range of from about 45.degree. C. to
about 250.degree. C., or a combination thereof. In one example, a
coating, such as a refinish coating, can be cured at aforementioned
ambient temperature. In another example a coating, such as an OEM
(Original Equipment Manufacturing) coating, can be cured at
aforementioned elevated temperature. In yet another example, a
coating can be cured for a certain period of time, such as a few
minutes to a few hours, at the ambient temperature, followed by
curing at elevated temperature.
[0068] In an embodiment, the coating process further comprises the
steps of:
[0069] applying a clear coating composition over the wet metallic
color coat layer to form a wet clear coat layer thereon; and
[0070] curing the wet metallic color coat layer and the wet clear
coat layer at same time.
[0071] After each wet coat layer is formed, an optional flashed
step can be performed to remove some or all of the solvents. In one
example, flashing can be performed after one wet metallic color
coat layer is formed. In another example, subsequent coating layers
can be directly applied over a previous wet coating layer without
the flashing step. The coating layers can be cured together at an
ambient temperature in a range of from about 15.degree. C. to about
45.degree. C., an elevated temperature in a range of from about
45.degree. C. to about 250.degree. C., or a combination thereof
[0072] In an embodiment, each coating layer is applied to have a
thickness in a range of from about 0.1 mil to about 2 mils (about
2.5 to about 50 microns).
[0073] The clear coat layer can provide further protection to the
substrate or provide further enhanced appearance, such as enhanced
gloss. Typical clearcoat can be suitable. In one example, suitable
clearcoat can include ChromaClear.RTM. available under trademark or
registered trademark from E.I du Pont de Nemours and Company,
Wilmington, USA.
[0074] The substrate can be a vehicle, vehicle parts, or a
combination thereof
[0075] Phosphated polymers have been used to provide passivation of
metallic pigments, such as aluminum flakes, such as those disclosed
in U.S. Pat. No. 4,675,358 issued Jun. 23, 1987 and in U.S. Pat.
No. 5,502,113 issued Mar. 26, 1996. The color pigments, however,
are not passivated.
[0076] Applicant unexpectedly discovered that by passivating the
color pigments that are essentially free from the metallic pigments
before mixing the passivated color pigments with the metallic
pigment into a coating composition, better color stability and less
gassing can be achieved especially for aqueous coating
compositions, such as the coating compositions that comprise in a
range of from about 20% to about 80% of water.
Examples
[0077] The present invention is further defined in the following
Examples. It should be understood that these Examples, while
indicating preferred embodiments of the invention, are given by way
of illustration only. From the above discussion and these Examples,
one skilled in the art can ascertain the essential characteristics
of this invention, and without departing from the spirit and scope
thereof, can make various changes and modifications of the
invention to adapt it to various uses and conditions.
Example A
[0078] Stabilized color pigment dispersion A was formed by mixing a
color pigment dispersion A with a phosphated polymer solution A
according to Table 1. The Color Pigment Dispersion A used for this
example is available from E. I. du Pont de Nemours and Company,
Wilmington, Del., USA and comprises 38.77% of water and 27.50% of
Red Iron Oxide pigment SICOTRANS.RTM. RED L 2818 under registered
trademark from BASF Aktiengesellschaft, Ludwigshafen, Germany. The
Color Pigment Dispersion A was essentially free from metallic
pigments.
TABLE-US-00001 TABLE 1 Stabilized color pigment dispersion A
(weight percent). Wt % Color Pigment Dispersion A 30.73 Phosphated
Polymer A: 64.00 Water 33.77%, 10% DMEA (dimethyl ethanol amine)
15.00% polyurethane emulsion dispersion .sup.(1) 7.03%, phosphate
polymer A .sup.(2) 8.0% bactericides and fungicides .sup.(3) 0.2%
Subtotal 64.00% Acrylic polymer .sup.(4) 2.10 10% DMEA 3.17 Total
100. .sup.(1) The polyurethane emulsion dispersion used was
available from E. I. du Pont de Nemours and Company, Wilmington,
DE, USA. .sup.(2) The phosphate polymer A used was the phosphated
graft acrylic polymer described in U.S. Pat. No. 5,502,113.
.sup.(3) The bactericides and fungicides used was MERGAL .RTM.
K10N, available under respective registered trademark from Troy
Corporation, Florham Park, New Jersey, USA. .sup.(4) The acrylic
polymer used was Rheotech 3000 acrylic polymer available from
COATEX Inc., CHESTER, SC, USA.
[0079] The phosphated polymer solution A was pre-blended before
mixing with the color pigment dispersion. The acrylic polymer,
Rheotech 3000 and amine reducer, dimethyl ethanol amine, can be
optional and were introduced to enhance pigment tone shelf life
stability. The polyurethane emulsion was introduced as a part of
binders for color base coat and can be selected based on the
binders of the coating.
Color Coating Composition A was a color coating having metallic
beige color and was prepared according to Table 2.
TABLE-US-00002 TABLE 2 Color Coating Composition A. Ingredients Wt
% Binder I .sup.(5) 10.55 Viscosity Balancer .sup.(6) 24.61
Aluminum Flakes .sup.(7) 53.10 Flatting Agent .sup.(8) 5.75 Red
Transoxide .sup.(9) 4.86 White LS .sup.(10) 0.79 Red Oxide
.sup.(11) 0.35 Total 100.00 The Color Coating Composition A was
adjusted to have 50% to 80% of water, percentage based on the total
weight of the Color Coating Composition A. Following Cromax Pro
.RTM. components available from E. I. du Pont de Nemours and
Company, Wilmington, DE, USA, under respective trademarks and
registered trademarks, were used for preparing the Color
Compositing Composition A: .sup.(5) WB2010 .TM.; .sup.(6) WB2030
.TM.; .sup.(7) WB1032 .TM.; .sup.(8) WB1050 .TM.; .sup.(9) The
Stabilized color pigment dispersion A prepared above; .sup.(10)
WB02 .TM.; and .sup.(11) WB84 .TM..
Example B
[0080] Stabilized color pigment dispersion B was formed by mixing a
color pigment dispersion B with a phosphated polymer solution B
according to Table 3. The Color Pigment Dispersion B used for this
example is available from E. I. du Pont de Nemours and Company,
Wilmington, Del., USA and comprises 47.05% of water and 14.25% of
Red Iron Oxide pigment SICOTRANS.RTM. RED L 2818 under registered
trademark from BASF Aktiengesellschaft, Ludwigshafen, Germany. The
Color Pigment Dispersion B was essentially free from metallic
pigments.
TABLE-US-00003 TABLE 3 Stabilized color pigment dispersion B
(weight percent). Wt % Color Pigment Dispersion B 50.2 Phosphated
Polymer B: 47.7 Water 21.62% 10% DMEA (dimethyl ethanol amine)
9.10% polyurethane emulsion dispersion .sup.(1) 12.78% phosphate
polymer B .sup.(12) 4.00% bactericides and fungicides .sup.(3) 0.2%
Subtotal 47.7% Acrylic polymer .sup.(4) 2.10 Total 100.0 .sup.(1),
(3) and .sup.(4) Same as that in Table 1. .sup.(12) The phosphate
polymer B used was the phosphated polymer described in U.S. Pat.
No. 4,675,358.
The phosphated polymer solution B was pre-blended before mixing
with the color pigment dispersion. The acrylic polymer, Rheotech
3000 and amine reducer, dimethyl ethanol amine, can be optional and
were introduced to enhance pigment tone shelf life stability. The
polyurethane emulsion was introduced as a part of binders for color
base coat and can be selected based on the binders of the coating.
Color Coating Composition B was a color coating having metallic
beige color and was prepared according to Table 4.
TABLE-US-00004 TABLE 4 Color Coating Composition B. Ingredients Wt
% Binder I .sup.(5) 10.55 Viscosity Balancer .sup.(6) 24.61
Aluminum Flakes .sup.(7) 53.10 Flatting Agent .sup.(8) 5.75 Red
Transoxide .sup.(13) 4.86 White LS .sup.(10) 0.79 Red Oxide
.sup.(11) 0.35 Total 100.00 The Color Coating Composition B was
adjusted to have 50% to 80% of water, percentage based on the total
weight of the Color Coating Composition B. .sup.(5)-(8) and
.sup.(10)-(11) same as that in Table 2. .sup.(13) The Stabilized
color pigmentation dispersion B prepared above.
The Color Coating Composition B was adjusted to have 50% to 80% of
water, percentage based on the total weight of the Color Coating
Composition B.
Comparative Example C
[0081] Comparative Dispersion C prepared by mixing the Color
Pigment Dispersion B with water, polyurethane emulsion, biocide,
and thickener according to Table 5 without phosphated polymers.
TABLE-US-00005 TABLE 5 Comparative Dispersion C (weight percent).
Wt % Color Pigment Dispersion B 50.20 Water 25.62 10% DMEA
(dimethyl ethanol amine) 9.10 polyurethane emulsion dispersion
.sup.(1) 12.78 bactericides and fungicides .sup.(3) 0.20 Acrylic
polymer .sup.(4) 2.10 Total 100.00 .sup.(1), (3) and .sup.(4) Same
as that in Table 1.
Comparative Coating Composition C was a color coating having
metallic beige color and was prepared according to Table 6.
TABLE-US-00006 TABLE 6 Comparative Coating Composition C.
Ingredients Wt % Binder I .sup.(5) 10.55 Viscosity Balancer
.sup.(6) 24.61 Aluminum Flakes .sup.(7) 53.10 Flatting Agent
.sup.(8) 5.75 Red Transoxide .sup.(14) 4.86 White LS .sup.(11) 0.79
Red Oxide .sup.(11) 0.35 Total 100.00 The Comparative Coating
Composition C was adjusted to have 50% to 80% of water, percentage
based on the total wieght of the Comparative Coating Composition C.
.sup.(5)-(8) and .sup.(10)-(11) same as that in Table 2. .sup.(14)
The Comparative Pigment Dispersion C prepared above;
The Comparative Coating Composition C was adjusted to have 50% to
80% of water, percentage based on the total weight of the
Comparative Coating Composition C.
Color Saturation and Color Stability
[0082] Color coating compositions A, B and C were each sprayed on
individual 4''.times.12'' E-coat panels via Sata spray gun (3000 RP
HVLP) at an air pressure of 30 psig to form one or more layers of
respective basecoat on each of the panels. Thickness of the
basecoat was in a range of from 0.4 to 0.6 mils (about 10 to 15
microns). No flash was performed between the coatings. A clear coat
was applied over each of the basecoat using ChromaClear.RTM. 72100S
available under trademark or registered trademark from E.I du Pont
de Nemours and Company, Wilmington, USA. The clearcoat was applied
over the basecoat after the last coating of the basecoat was
completely flat. Coatings were applied and dried at room
temperatures in a range of from 20.degree. C. to 25.degree. C. The
panels were dried and then evaluated for their initial color
positions. Similar spray panels were prepared after the coating
compositions were stored on shelf for a certain period of time as
indicated in Table 7. The colors were measured using a commercially
available X-rite instrument from X-Rite Incorporated, Grand Rapids,
Mich., USA.
TABLE-US-00007 TABLE 7 Color Saturation and Stability. Panels with
Coating Initial 24 hr 1 week Compositions a b a b a b Ex 1 (Panel
with Color 2.7 11.4 3.0 11.0 2.9 10.7 Coating Composition A) Ex 2
(Panel with Color 3.1 10.6 3.1 10.2 3.2 10.2 Coating Composition B)
Comp 1 (Panel with 2.9 8.5 3.0 7.9 3.0 8.0 Comparative Coating
Composition C)
The comparative coating composition C showed an initial b value, or
yellowness, of 8.5, which was 2 to 3 units less saturated than the
coating compositions A and B. This color loss was visible and
undesirable. The comparative coating composition C also showed
color loss after 24 hours with the b value from 8.5 initial to 7.9
at 24 hours. Color coating compositions A and B showed more
saturated colors without color loss after storing the color coating
compositions for one week.
Gassing Stability
[0083] The stabilized color pigment dispersion A, B and the
Comparative Dispersion C prepared above were mixed with aluminum
pigments according to Table 8 to determine their gassing
stability.
TABLE-US-00008 TABLE 8 Mixtures of dispersions and aluminum
pigments (wt %). Ex Ex Ex Ex Comp Comp 3 4 5 6 2 3 Stabilized color
30 30 pigment dispersion A .sup.(15) Stabilized color 30 30 pigment
dispersion B .sup.(16) Comparative 30 30 Dispersion C .sup.(17)
Aluminum 10 10 10 pigments 1 .sup.(18) Aluminum 10 10 10 pigments 2
.sup.(19) Binder I .sup.(5) 60 60 60 60 60 60 Total 100 100 100 100
100 100 .sup.(5)Same as that in Table 2. .sup.(15)From Example A
(Table 1). .sup.(16)From Example B (Table 3). .sup.(17)From
Comparative Example C (Table 5). .sup.(18)-(19)The Aluminum
pigments 1 used was WB1032 .TM. and Aluminum pigments 2 used was
WB1078 .TM., all available as Cromax Pro .RTM. components from E.
I. du Pont de Nemours and Company, Wilmington, DE, USA, under
respective trademarks and registered trademarks.
Specimens of 15 grams from each of the above mixtures in
triplicates were filled into a 20 ml vial and then sealed with a
rubber cap. The sealed vials were placed in 40.degree. C. oven for
24 hours. A needle pressure gauge was then penetrated into each of
the sealed vials for pressure build-up measurements after the vials
were taken out of the oven and cooled to room temperature at about
25.degree. C. Gas pressure data measured as psig (pound-force per
square inch gauge) in triplicates are shown in Table 9. The
comparative dispersion C showed a significant pressure build-up
when mixed with aluminum pigments due to hydrogen gas generation
via reactions of aluminum flakes and iron oxide pigments. The
stabilized color pigment dispersions A and B had no gas generation
problems.
TABLE-US-00009 TABLE 9 Gassing Data (psig). Specimen 1 Specimen 2
Specimen 3 Ex 3 -1.32 -0.16 0.46 Ex 4 -0.14 0.34 -1.42 Ex 5 0.06
-0.92 -1.1 Ex 6 -1.16 -0.66 -0.64 Comp 2 8.08 6.2 13.22 Comp 3
-0.82 11.9 3.68
* * * * *